RESUMEN
The identification of mutations in the transcriptional repressor methyl-CpG-binding protein 2 (MECP2) gene in Rett Syndrome (RTT) suggests that an inappropriate release of transcriptional silencing may give rise to RTT neuropathology. Despite this progress, the molecular basis of RTT neuropathogenesis remains unclear. Using multiple cDNA microarray technologies, subtractive hybridization, and conventional biochemistry, we generated comprehensive gene expression profiles of postmortem brain tissue from RTT patients and matched controls. Many glial transcripts involved in known neuropathological mechanisms were found to have increased expression in RTT brain, while decreases were observed in the expression of multiple neuron-specific mRNAs. Dramatic and consistent decreases in transcripts encoding presynaptic markers indicated a specific deficit in presynaptic development. Employing multiple clustering algorithms, it was possible to accurately segregate RTT from control brain tissue samples based solely on gene expression profile. Although previously achieved in cancers, our results constitute the first report of human disease classification using gene expression profiling in a complex tissue source such as brain.
Asunto(s)
Encéfalo/enzimología , Proteínas Cromosómicas no Histona , Proteínas de Unión al ADN/biosíntesis , Perfilación de la Expresión Génica , Proteínas del Tejido Nervioso/biosíntesis , Neuronas/metabolismo , Cambios Post Mortem , Proteínas Represoras , Síndrome de Rett/genética , Adolescente , Adulto , Algoritmos , Secuencia de Aminoácidos , Southern Blotting , Causas de Muerte , Niño , Preescolar , Proteínas de Unión al ADN/genética , Compensación de Dosificación (Genética) , Femenino , Humanos , Proteína 2 de Unión a Metil-CpG , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/genética , Neuroglía/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/biosíntesis , Síndrome de Rett/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Técnica de SustracciónRESUMEN
We have succeeded in stably maintaining the entire genome of SIVmac239 as a plasmid clone. Supercoiled proviral plasmid DNA was inoculated intramuscularly into two adult rhesus macaques and into a neonate. All three animals became viremic and seroconverted. Viral kinetics were followed prospectively by quantitative competitive reverse transcriptase polymerase chain reaction (QC-RT-PCR), measurement of proviral DNA load in peripheral blood mononuclear cells (PBMCs) by PCR, and virus isolation by cocultivation. The infant developed high virus loads and succumbed to AIDS and SIV-associated nephropathy at 10 weeks postinoculation. Both adults are still living but have progressed to AIDS; one adult has also developed severe thrombocytopenia. We conclude that infection through intramuscular inoculation of cloned plasmid DNA encoding the entire proviral genome is reproducible and will provide a useful tool for studying viral pathogenesis.
Asunto(s)
Plásmidos/genética , Síndrome de Inmunodeficiencia Adquirida del Simio/fisiopatología , Virus de la Inmunodeficiencia de los Simios/patogenicidad , Viremia/virología , Animales , Animales Recién Nacidos , ADN Viral/sangre , Macaca mulatta , Provirus , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/genética , Subgrupos de Linfocitos T/inmunología , Carga ViralRESUMEN
A substantial risk in using live attenuated, multiply deleted viruses as vaccines against AIDS is their potential to induce AIDS. A mutant of the simian immunodeficiency virus (SIV) with large deletions in nef and vpr and in the negative regulatory element induced AIDS in six of eight infant macaques vaccinated orally or intravenously. Early signs of immune dysfunction were seen in the remaining two offspring. Prolonged follow-up of sixteen vaccinated adult macaques also showed resurgence of chronic viremia in four animals: two of these developed early signs of disease and one died of AIDS. We conclude that this multiply deleted SIV is pathogenic and that human AIDS vaccines built on similar prototypes may cause AIDS.
Asunto(s)
Envejecimiento/inmunología , Vacunas contra el SIDAS , Síndrome de Inmunodeficiencia Adquirida del Simio/prevención & control , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Vacunas Atenuadas/inmunología , Líquido Amniótico/virología , Animales , Progresión de la Enfermedad , Femenino , Productos del Gen nef/genética , Productos del Gen vpr/genética , Inmunidad Mucosa , Macaca mulatta , Masculino , Datos de Secuencia Molecular , Embarazo , Complicaciones Infecciosas del Embarazo/inmunología , Complicaciones Infecciosas del Embarazo/prevención & control , Vacunas contra el SIDAS/inmunología , Eliminación de Secuencia , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunologíaRESUMEN
We report the complete nucleotide sequence of the genome of Rauscher murine leukemia virus (R-MuLV), the replication-competent helper virus present in the Rauscher virus complex, and its phylogenetic relationship with other murine leukemia virus genomes. An overall sequence identity of 97.6% was found between R-MuLV and the Friend helper virus (F-MuLV), and the two viruses were closely related on the phylogenetic trees constructed from either gag, pol, or env sequences. Moloney murine leukemia virus (Mo-MuLV) was the next closest relative to R-MuLV and F-MuLV on all trees, followed by Akv and radiation leukemia virus (RadLV). The most distantly related helper virus was Hortulanus murine leukemia virus (Ho-MuLV). Interestingly, Cas-Br-E branched with Mo-MuLV on the gag and pol trees, whereas on the env tree, it revealed the highest degree of relatedness to Ho-MuLV, possibly due to an ancient recombination with an Ho-MuLV ancestor. In summary, a phylogenetic analysis involving various MuLVs has been performed, in which the postulated close relationship between R-MuLV and F-MuLV has been confirmed, consistent with the pathobiology of the two viruses.